"UK moulding recommendation for small enclosures?"
There must be 10 companies within a 10 mile radius, in the UK. I used to be next door to one such, running 24/7, with 1 machine, churning out plastic cups. I am sure he was the cheapest around, in that business.
"I find relationships or "guanxi" apply only to the People which Westerners are not. After the initial honeypot, they are opportunists and will cheapen things to no limits- as you let them, and jack up prices once you are hooked and in need of their parts."
Yes I think they often just hate us. But hey you could say that about so many scenarios. Do you think the Spanish like the Brits living there, or the French like the Brits buying up the old barns? Those Brits are busy moving back to the UK because they found that despite learning the language and making some effort they were never accepted. Whereas in the UK European foreigners are normally taken at face value.
But the real problem in modern China is that it is fast moving and anybody enterprising is trying to make a fast buck. The average company "we" deal with has say 100 people and 1 of them speaks English, and if that one person (who is in high demand) moves on (which they do every 6 months) you have to almost start again. And people don't care about screwing somebody over. I've found the Chinese totally shameless. But as long as they are cheap they will get business.
"Of course it's our fault because the control drawings did not specify EVERYTHING"
You you have to be specific in the spec. If possible, free issue the materials. I have bought 6000 cores and sent only 3000 to China to be wound, so if they vanish before they ship, I haven't lost all the cores (16 week lead time)
", they pay the same as everyone else for materials"
They do NOT. They get almost everything for much less. Plastics, cables, metal parts. All much cheaper. Here in the West everybody in business is trying to make 100k+ so they can have 3 cars outside the house and kids in a private school.
Western chip companies sell chips for far less in China than in the West. They always have done. But only to big volume mfgs. Intel pricing for example was perhaps 30% of Western pricing. I have come across companies there who managed to buy chips there and ship them to here but today they are hard to find.
Notably, metalwork is vastly cheaper in China. Here, any sort of metal enclosure costs a few quid - unless you can knock it out with a complicated press tool in one go. Even 1k+ it is a few quid. In China it is under $1.
"How many companies in the UK are making transformers?"
Those are labour intensive, so they went to China. But also the Chinese can buy the ferrites for a lot less, from no-name companies out there. Compare the price of an RJ45 with integral magnetics (e.g. Hanrun) with Western-made versions (Wurth is a good example of grossly overpriced stuff). But even Hanrun are being counterfeited at about 1/3 of the price...